CLICing into action

Putting its acronym into action, the Compact Linear Collider (CLIC) collaboration is testing its first compact accelerator module in the CTF3 test facility. Fed by high-power waveguides, cables and cooling tubes, the module has all the functions of future CLIC modules and allows the experts to test all the features, including frequency, losses, damping, acceleration and deceleration.


The new CLIC module in the CTF3 test facility.

CLIC is one of the potential follow-up projects to the LHC, alongside the International Linear Collider (ILC) and the Future Circular Collider (FCC) studies. Instead of smashing protons into protons, it is designed to collide electrons with positrons. Following the publication of its CDR in 2012, the CLIC collaboration entered the project preparation phase - testing its unique technology, making improvements and taking a closer look at the cost of the individual components.

This is where the new module comes in. While many of the techniques and technologies needed for and around CLIC’s sophisticated drive-beam acceleration have already been tested individually, this module is the first opportunity to bring all the elements together. The module has been integrated into the test facility and has all the features of future CLIC modules: CLIC-type alignment systems, accelerating structures with higher-order mode damping and integrated diagnostics tools like wakefield monitors.

Now integrated, the CLIC researchers have begun to test it with beam. “It’s a complex system, and our first results look promising,” says Steffen Doebert, who is part of the team that developed the module. “We have to check all the connections and calibrate the module before installing a second super accelerating structure consisting of two accelerator units.” With the help of the diagnostic tools integrated into the module, which can detect very small fields, the CLIC team knows where the beam is at any time within the structure. A very precise alignment system developed by CERN's metrology service and a silicon carbide support that can be adjusted in all directions allow the researchers to perform very accurate beam-based corrections. “After all we need to be precise down to ten microns,” says Doebert.

With these good results in their hands, the members of CLIC met at CERN from 26 to 30 January for their annual collaboration meeting. You can find additional information about the meeting here.

by Barbara Warmbein